Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Combustors often operate at high temperatures that may exceed 2,500 degrees Fahrenheit. Typical turbine combustor configurations expose turbine blade assemblies to these high temperatures. As a result, turbine blades and turbine vanes must be made of materials capable of withstanding such high temperatures. Turbine blades, vanes and other components often contain cooling systems for prolonging the life of these items and reducing the likelihood of failure as a result of excessive temperatures.
Typically, a midframe case extends between a compressor and in some confirguations between a compressor case and an exhaust case. The midframe case often channels compressor bleed air to the turbine rotor assembly. As the midframe shell air temperature exceeds 450 degrees Celsius, a majority of the commonly used steel alloys become creep limited. Over time, the materials become embrittled and suffer from permanent creep deformation at temperatures above 450 degrees Celsius. Thus, as design requirements increase and peak compressor discharge temperatures approach 550 degrees Celsius, meeting the 160,000 hour and 5,000 start component life cycle thresholds becomes very unlikely using standard alloys and conventional technology.